Temporal stability of acute stress-induced changes in leukocyte subsets and cellular adhesion molecules in older...

This study investigated the temporal stability of enumerative immune and catecholamine responses to acute psychosocial stress in 67 Alzheimer's caregivers ages 56-82 years (45 women and 22 men) who were required to prepare and deliver two 3-min speeches on three occasions at 2-week and 6-week intervals. All leukocyte subsets and adhesion molecules (CD62L and CD11a) changed significantly from rest to postspeak at each of the three testing sessions (p's <.0005). Responses showed moderate to high temporal stability across baseline and absolute task values (r's =.65-.96). Reliability was predictably lower for both forms of change scores (r's = -.16-.64). The level of temporal stability achieved is comparable to that seen previously in younger adults, indicating that acute psychosocial stress produces reliable changes in circulating leukocytes and cell adhesion molecules in older adults.